The present invention generally relates to rotary recording medium reproducing apparatuses capable of placing and leaving a rotary information recording medium in a state possible for reproduction within the reproducing apparatus when a jacket having a lid for accommodating the recording medium therein is inserted into and then pulled out from within the reproducing apparatus, and also capable of incasing the recording medium within the jacket so that the recording medium can be obtained outside the reproducing apparatus together with the jacket, when the empty jacket is inserted into and then pulled out from within the reproducing apparatus. The present invention more particularly relates to the above type of a rotary recording medium reproducing apparatus provided with a jacket opening enlarging device having a locking mechanism which locks upper and lower enlarging members for enlarging an opening of the jacket which is inserted into the reproducing apparatus, when the rotary recording medium is loaded into and unloaded from the reproducing apparatus.
Conventionally, in an apparatus for reproducing a rotary recording medium (referring to a video disc, PCM audio disc, and the like, and hereinafter simply referred to as a disc), there are types of apparatuses in which a disc is reproduced when the disc is loaded upon clamping and placing of the disc within the reproducing apparatus, by inserting into and then pulling out a jacket (disc case) which has a lid and accommodates a disc therein, from within the reproducing apparatus. As a conventional apparatus of this type, a reproducing apparatus was proposed in a U.S. patent application Ser. No. 231,868 filed Feb. 5, 1981, entitled "DISC-SHAPED RECORDING MEDIUM REPRODUCING APPARATUS" in which the assignee is the same as that of the present application. This previously proposed reproducing apparatus operates together with a disc case comprising a jacket which has a space for accommodating a disc and an opening for allowing the disc to go in and out of the jacket, and a lid member inserted through the opening of the jacket for closing the opening of the jacket, where the reproducing apparatus comprises an inserting opening through which the case is inserted, a turntable for rotating the disc, holding means for holding at least one of the disc and the lid member provided at an innermost part on the opposite side from the inserting opening with respect to the turntable, a jacket opening enlarging device provided in the vicinity of the inserting opening, capable of moving over the turntable between the position in the vicinity of the inserting opening and the innermost part of the reproducing apparatus, for enlarging the opening of the jacket by entering inside cutouts of the lid member upon insertion of the jacket into the reproducing apparatus through the inserting opening, lowering and raising means for lowering the disc to a position where the disc is placed on the turntable from a holding position where a disc is held by the holding means upon starting of the reproduction, and raising the disc to the holding position from the turntable upon finishing or discontinuing of the reproduction, a reproducing transducer for reproducing the disc placed on the turntable, and moving means for moving the reproducing transducer from a waiting position to a reproducing position with respect to the disc.
In the above previously proposed reproducing apparatus, the jacket opening enlarging device is constructed on that upper and lower enlarging members are respectively provided in a horizontal manner. Accordingly, when the jacket opening enlarging device is positioned at the case inserting opening side of the reproducing apparatus, the upper and lower enlarging members are respectively rotated towards directions so as to mutually close upon each other.
However, in the previously proposed reproducing apparatus, means and the like for restricting the rotation of the upper and lower enlarging members in the enlarging direction, were not provided. Hence, when an operator inserts a finger and the like inside the case inserting opening, for example, the upper and lower enlarging members are respectively rotated in the enlarging direction, and the finger and the like is inserted into the reproducing apparatus. Especially during a reproducing mode in which the disc is rotating at a high speed together with the turntable, there was a danger in that the finger tip could be injured upon contact with the turntable which is rotating at a high speed when a finger is inserted. Furthermore, there was a disadvantage in that a foreign substance could possibly enter within the reproducing apparatus by respectively rotating the upper and lower enlarging members towards the enlarging direction.